This invention relates to an improved device and method for locating and marking blood vessels in a body and, more particularly, to a self-contained, portable device which non-invasively locates vessels and visually marks the skin accordingly.
One of the most frequently performed medical procedures is the insertion of a needle into a live human body for the purpose of drawing blood, inserting a catheter, performing diagnostic tests, etc. Despite the frequency with which this task is undertaken, accurate insertion of a needle is often difficult where the position of the desired vessel is not readily apparent or where the vessel is very small. This difficulty often results in several unsuccessful attempts to penetrate the desired vessel--a result which obviously increases the discomfort experienced by the patient.
Several devices for locating blood vessels in a live human body have been proposed in the prior art, reference being made to U.S. Pat. No. 5,678,555 and the patents discussed therein. The devices described in the referenced patents transmit and receive ultrasonic or infrared signals to locate the position of a blood vessel. The system proposed in the '555 patent further provides for marking the skin immediately covering the detected vessel. The system, however, requires the use of several electronic components for locating and then temporarily marking the skin. It should also be noted that the accuracy of the prior art devices is partially dependent upon the steadiness of the medical personnel in moving and positioning the monitoring or marking equipment.
Although assumably effective in operation, none of the devices proposed in the prior art provides a completely self-contained, portable device which non-invasively locates and automatically marks the position of a blood vessel. It is thus desirable to have a single device with all of the above described advantages. It is further desirable to have such a device which can locate and mark vessels while remaining in a fixed position (e.g., about a patient's arm).